Module org.apache.jena.core
Package org.apache.jena.reasoner.rulesys

Class FBRuleReasoner

java.lang.Object
org.apache.jena.reasoner.rulesys.FBRuleReasoner
All Implemented Interfaces:
Reasoner, RuleReasoner
Direct Known Subclasses:
GenericRuleReasoner, OWLFBRuleReasoner, RDFSFBRuleReasoner
public class FBRuleReasoner extends Object implements RuleReasoner
Rule-based reasoner interface. This is the default rule reasoner to use. It supports both forward reasoning and backward reasoning, including use of forward rules to generate and instantiate backward rules.

  • Constructor Details

    • FBRuleReasoner

      public FBRuleReasoner(List<Rule> rules)
      Constructor. This is the raw version that does not reference a ReasonerFactory and so has no capabilities description.
      Parameters:
      rules - a list of Rule instances which defines the ruleset to process

    • FBRuleReasoner

      public FBRuleReasoner(ReasonerFactory factory)
      Constructor
      Parameters:
      factory - the parent reasoner factory which is consulted to answer capability questions

    • FBRuleReasoner

      public FBRuleReasoner(ReasonerFactory factory, Resource configuration)
      Constructor
      Parameters:
      factory - the parent reasoner factory which is consulted to answer capability questions
      configuration - RDF node to configure the rule set and mode, can be null

    • FBRuleReasoner

      public FBRuleReasoner(List<Rule> rules, ReasonerFactory factory)
      Constructor
      Parameters:
      rules - a list of Rule instances which defines the ruleset to process
      factory - the parent reasoner factory which is consulted to answer capability questions

  • Method Details

    • addRules

      public FBRuleReasoner addRules(List<Rule> rules)
      Add the given rules to the current set and answer this Reasoner. Provided so that the Factory can deal out reasoners with specified rulesets. There may well be a better way to arrange this.

    • getReasonerCapabilities

      public Model getReasonerCapabilities()
      Return a description of the capabilities of this reasoner encoded in RDF. These capabilities may be static or may depend on configuration information supplied at construction time. May be null if there are no useful capabilities registered.
      Specified by:
      getReasonerCapabilities in interface Reasoner

    • getBoundSchema

      public Graph getBoundSchema()
      Answer the schema graph bound into this reasoner, or null if there isn't one. (Added mainly for testing purposes, which is why it isn't part of the Reasoner API.)

    • addDescription

      public void addDescription(Model configSpec, Resource base)
      Add a configuration description for this reasoner into a partial configuration specification model.
      Specified by:
      addDescription in interface Reasoner
      Parameters:
      configSpec - a Model into which the configuration information should be placed
      base - the Resource to which the configuration parameters should be added.

    • supportsProperty

      public boolean supportsProperty(Property property)
      Determine whether the given property is recognized and treated specially by this reasoner. This is a convenience packaging of a special case of getCapabilities.
      Specified by:
      supportsProperty in interface Reasoner
      Parameters:
      property - the property which we want to ask the reasoner about, given as a Node since this is part of the SPI rather than API
      Returns:
      true if the given property is handled specially by the reasoner.

    • bindSchema

      public Reasoner bindSchema(Graph tbox) throws ReasonerException
      Precompute the implications of a schema graph. The statements in the graph will be combined with the data when the final InfGraph is created.
      Specified by:
      bindSchema in interface Reasoner
      Parameters:
      tbox - the ontology axioms or rule set encoded in RDF
      Returns:
      a reasoner instace which can be used to process a data graph
      Throws:
      ReasonerException - if the reasoner cannot be bound to a rule set in this way, for example if the underlying engine can only accept a single rule set in this way and one rule set has already been bound in of if the ruleset is illformed.

    • bindSchema

      public Reasoner bindSchema(Model tbox) throws ReasonerException
      Precompute the implications of a schema Model. The statements in the graph will be combined with the data when the final InfGraph is created.
      Specified by:
      bindSchema in interface Reasoner
      Parameters:
      tbox - the ontology axioms or rule set encoded in RDF
      Returns:
      a reasoner instace which can be used to process a data graph
      Throws:
      ReasonerException - if the reasoner cannot be bound to a rule set in this way, for example if the underlying engine can only accept a single rule set in this way and one rule set has already been bound in of if the ruleset is illformed.

    • bind

      public InfGraph bind(Graph data) throws ReasonerException
      Attach the reasoner to a set of RDF data to process. The reasoner may already have been bound to specific rules or ontology axioms (encoded in RDF) through earlier bindRuleset calls.
      Specified by:
      bind in interface Reasoner
      Parameters:
      data - the RDF data to be processed, some reasoners may restrict the range of RDF which is legal here (e.g. syntactic restrictions in OWL).
      Returns:
      an inference graph through which the data+reasoner can be queried.
      Throws:
      ReasonerException - if the data is ill-formed according to the constraints imposed by this reasoner.

    • setRules

      public void setRules(List<Rule> rules)
      Set (or change) the rule set that this reasoner should execute.
      Specified by:
      setRules in interface RuleReasoner
      Parameters:
      rules - a list of Rule objects

    • getRules

      public List<Rule> getRules()
      Return the list of Rules used by this reasoner
      Specified by:
      getRules in interface RuleReasoner
      Returns:
      a List of Rule objects

    • loadRules

      public static List<Rule> loadRules(String fileName)
      Answer the list of rules loaded from the given filename. May throw a ReasonerException wrapping an IOException.

    • tablePredicate

      public void tablePredicate(Node predicate)
      Register an RDF predicate as one whose presence in a goal should force the goal to be tabled. This is better done directly in the rule set.

    • setDerivationLogging

      public void setDerivationLogging(boolean logOn)
      Switch on/off derivation logging. If set to true then the InfGraph created from the bind operation will start life with recording of derivations switched on. This is currently only of relevance to rule-based reasoners.

      Default - false.

      Specified by:
      setDerivationLogging in interface Reasoner

    • setTraceOn

      public void setTraceOn(boolean state)
      Set the state of the trace flag. If set to true then rule firings are logged out to the Logger at "INFO" level.

    • isTraceOn

      public boolean isTraceOn()
      Return the state of the trace flag.If set to true then rule firings are logged out to the Log at "INFO" level.

    • setParameter

      public void setParameter(Property parameter, Object value)
      Set a configuration parameter for the reasoner. The supported parameters are:
      • PROPderivationLogging - set to true to enable recording all rule derivations
      • PROPtraceOn - set to true to enable verbose trace information to be sent to the logger INFO channel
      Specified by:
      setParameter in interface Reasoner
      Parameters:
      parameter - the property identifying the parameter to be changed
      value - the new value for the parameter, typically this is a wrapped java object like Boolean or Integer.
      Throws:
      IllegalParameterException - if the parameter is unknown

    • getGraphCapabilities

      public Capabilities getGraphCapabilities()
      Return the Jena Graph Capabilities that the inference graphs generated by this reasoner are expected to conform to.
      Specified by:
      getGraphCapabilities in interface Reasoner